IK Multimedia is offering SampleTank 2.5 XL for $39.99.
SampleTank 2.5 XL is a 16-part multitimbral MIDI workstation, which runs either standalone, or as a DAW plug-in (VST, RTAS, AU), and comes with a huge collection of instruments including acoustic pianos, drums, strings, basses, synths — you name it, plus a large library of loops & patterns. There are 33 built-in studio effects and its collection can be greatly expanded.
SampleTank has an iPhone and iPad version and it's also 70% off - $5.99 for a limited time. SampleTank for iPhone & iPad is a versatile sound & groove workstation with over 500 instrument sounds in 16 categories, 1,000+ patterns, & a built-in 4-track MIDI recorder. Plus it's Audiobus compatible.